For months, Democrat Casey enjoyed a commanding lead of 18 or more percentage points over Republican Smith. But independent polls in recent days suggest Smith has cut that lead in half. One poll puts the gap at a mere six percentage points.

Given all the numbers from various polls, it's unlikely the Senate race is that close, but it has tightened. Handicappers at The Washington Post on Wednesday moved it from "solidly Democrat" to "lean Democrat," saying the latest numbers suggest the race is "firmly in play."

President Barack Obama, meanwhile, continues to enjoy a double-digit lead over Mitt Romney in the state.A Quinnipiac University survey of likely voters released Wednesday shows Casey ahead of Smith by six percentage points, and Obama ahead of Romney by 12. Quinnipiac showed Smith trailing by 18 on Aug. 1.

A Franklin & Marshall College poll also out Wednesday shows Casey with a 10-point lead among likely voters. And last week's latest The Morning Call/Muhlenberg College poll had Casey 12 points up. Libertarian Rayburn Smith also is on the ballot.

"I think the conclusion I would get by looking at the polls in whole is that the race has become more competitive," Muhlenberg pollster Chris Borick said. "But how competitive is uncertain."

The Casey-Smith Senate contest has been almost entirely ignored nationally. A win by Casey, a son of former Gov. Robert P. Casey, has been considered a foregone conclusion.

Smith, a farmer turned coal executive whose only political experience before running for the U.S. Senate was a stint as a township supervisor in the 1970s and as a GOP donor, has run a relentless statewide TV ad campaign.Smith's commercials have been a combination of positive ads showing him as a blue-collar average guy, and negative spots against Casey's record. And Smith's done it largely with his own money.

Smith has massively outspent Casey on TV, including in Philadelphia and the suburban counties, where Casey has spent no money at all. Meanwhile, Romney hasn't run a single TV ad in Pennsylvania.

Recent Pennsylvania polls show Casey at least as far ahead of Smith as Obama is of Romney. Quinnipiac's number -- just six points -- is unique.

Quinnipiac pollster Peter Brown speculated about why Smith may be doing better than Romney in Pennsylvania.Obama's effort to brand Romney as an out-of-touch millionaire has had an effect on working class voters, Brown said. Those same working-class voters, dubbed "Reagan Democrats" for their support of the former president, might like what they see in Smith's TV ads.

G. Terry Madonna, F&M's pollster, said that in Pennsylvania history there have been times that conservative Democrats have put a Democrat in the White House while voting for a Republican for Congress. But he sees less ticket-splitting because "of the hardening of partisan lines."

Smith may be tapping the nation's anti-Congress sentiment.

Obama's job approval and favorable numbers are much higher than those for Congress. In the F&M poll, Obama has 50 percent favorableness, compared with 37 percent for Casey. And nearly a quarter of Pennsylvania voters said they didn't know enough about Casey to form an opinion.

Still, Madonna said he doesn't think Casey should worry much. "I'm looking for something to show why Casey could lose," Madonna said. "What is it?"

Both the Franklin & Marshall and Quinnipiac polls found Obama crossing the 50 percent support threshold in Pennsylvania. In the former, he bests Romney 52 percent to 43 percent, and in the latter he's ahead 54 to 42 percent.

Romney's hurdle is an inability to convince everyday voters that he can connect with them. In the F&M poll, 59 percent said Obama best understands the concerns of ordinary Americans, compared with 32 percent who said Romney did.

In the Quinnipiac survey, voters were asked whether each candidate "cares about the needs and problems of people like you." While 60 percent said Obama does, 38 percent said Romney does.

Last week surveys done by Susquehanna Polling & Research put Pennsylvania's presidential race within the margin of error. Susquehanna attributed the difference in part to a different assumption about who will vote. The polling firm predicts a lower overall turnout than in 2008, and a higher turnout among Republican voters.